Revision total knee arthroplasty: Management of periprosthetic femur fracture around total knee arthroplasty

Distal femur periprosthetic fractures are increasing in incidence and provide unique challenges for the orthopedic surgeon when considering treatment. A majority of these fractures are low velocity mechanism in a patient with osteoporosis. The Rorabeck and Lewis classification not only provides a descriptive classification but also correlates with treatment options. These fractures are typically treated operatively due to importance of early mobilization on morbidity and mortality in this patient population. Type 1 and 2, implant stable fractures, can be fixed utilizing locked plating or intramedullary nailing while type 3, implant unstable, typically requires revision of femoral component. Operative fixation technique is based on soft tissue considerations, bone stock of distal fracture fragment, implant availability, and other ipsilateral hardware or pathology present. Complexity of revision arthroplasty will depend on degree of comminution, previous implant type, ligamentous stability, and patient's functional level. As with any revision knee arthroplasty, technique should minimize bone removed and level of constraint should be appropriate for balance. Allograft combined with prosthesis or as an adjunct with internal fixation is a consideration that can be useful when inadequate bone stock or healing potential is a concerns. When treated appropriately, surgical intervention can facilitate early mobilization while leading to a high level of satisfaction.